ELECTRONIC DEVICE AND RELATED METHOD AND MACHINE READABLE STORAGE MEDIUM
An embodiment of the invention provides a method performed by an electronic device. According to the method, the electronic device first receives a shutter instruction. Then, in response to the shutter instruction, the electronic device automatically captures a plurality of images of a scene using a plurality of different focal distances, respectively.
Latest MEDIATEK INC. Patents:
- METHOD FOR IMPLICITLY SIGNALING TRANSMIT SWITCHING CONFIGURATION OF MULTIPLE OPERATING BANDS AND ASSOCIATED WIRELESS COMMUNICATION DEVICE
- WIRELESS DEVICE CONTROL CIRCUIT WITH IDENTICAL MODULARIZED INTERNAL CIRCUIT ARCHITECTURE FOR DIFFERENT PROCESSING, AND ASSOCIATED WIRELESS COMMUNICATIONS DEVICE
- SEMICONDUCTOR STRUCTURE
- FREQUENCY CALIBRATION CIRCUIT AND METHOD FOR CALIBRATING OSCILLATION FREQUENCY OF CONTROLLABLE OSCILLATOR
- PHASE ERROR COMPENSATION CIRCUIT AND METHOD FOR COMPENSATING PHASE ERROR BETWEEN REFERENCE CLOCK AND FEEDBACK CLOCK
1. Technical Field
The invention relates generally to an electronic device capable of capturing images, and more particularly, to an electronic device capable of capturing images and allowing its user to refocus captured images.
2. Related Art
An electronic device capable of capturing images has a set of lens that guides some of the light coming from a scene onto an image sensor. If the lens set has at least one piece of lens that is movably mounted in the electronic device, the electronic device may have a focal distance that is adjustable. Even when the electronic device remains still, the electronic device's focus may be changed to different parts of the scene by changing the position of the movable lens within the electronic device.
If objects in the scene have different distances away from the electronic device, the electronic device may need to focus on only some parts of the scene and leave the other parts out of focus. The out-of-focus parts of the scene may seem blurred in the captured image and the user may not be able to refocus, i.e. change the focus of, the already captured image.
SUMMARYAn embodiment of the invention provides a method performed by an electronic device. According to the method, the electronic device first receives a shutter instruction. Then, in response to the shutter instruction, the electronic device automatically captures a plurality of images of a scene using a plurality of different focal distances, respectively.
An embodiment of the invention provides an electronic device. The electronic device includes a user interface, an actuator, an image sensor, a storage device, and a processor. The processor is coupled to the user interface, the actuator, the image sensor, and the storage device. The processor is configured to: in response to a shutter instruction the user interface receives, automatically control the actuator to enable the electronic device to get a plurality of focal distances, the image sensor to capture a plurality of images of a scene using the focal distances, respectively, and the storage device to store the images.
An embodiment of the invention provides a machine readable storage medium. The machine readable storage medium stores executable program instructions which when executed cause an electronic device to perform a method. The method includes: receiving a shutter instruction; and automatically capturing a plurality of images of a scene using a plurality of different focal distances, respectively, in response to the shutter instruction.
Other features of the present invention will be apparent from the accompanying drawings and from the detailed description which follows.
The invention is fully illustrated by the subsequent detailed description and the accompanying drawings, in which like references indicate similar elements.
The user interface 110 allows the electronic device 100 to interact with the user. For example, to receive shutter instructions or other kinds of instructions from the user, the user interface 110 may include or be connected to a mechanical shutter button, a touch pad, or a touch screen, or even a microphone for receiving voice commands. To display an image, the user interface 110 may include or be connected to a screen, a touch screen, a computer monitor, a television, or a projector. The actuator 120 may enable the electronic device 100 to get any one of several different focal distances, e.g. by changing the position of the image sensor 130 or a lens of the electronic device 100. The image sensor 130 may capture an image of a scene by detecting light that comes from the scene and eventually reaches the image sensor 130. The storage device 140 may store images captured by the image sensor 130. Furthermore, the storage device 140 may storage some executable program instructions. When being executed by the processor 150, some of the program instructions may cause the electronic device 100 to perform any of the methods described below. As a result, the processor 150 may be configured to control the components of the electronic device 100 to perform any of the methods described below. The program instructions may also be stored in another machine readable storage medium, such as an optical disc, a hard disk drive, a solid-state drive, or a flash memory.
The electronic device 100 may complete step 240 within a few seconds, without the user's involvement. In other words, the electronic device 100 may perform step 240 devoid of user intervention. This feature may reduce the user's waiting time and the risk that the objects in the scene or the electronic device 100 moves during step 240.
For example, at step 240, the processor 150 may automatically control the actuator 120 to enable the electronic device 100 to get the focal distances one by one, the image sensor 130 to capture the images at the focal distances, respectively, and the storage device 140 to store the images. In doing so, the processor 150 may control the actuator 120 to start from a maximum one of the focal distances and gradually move toward a minimum one of the focal distances, or from the minimum focal distance toward the maximum one.
An electronic device having access to the images captured at step 240 may conduct some post-production activities on the images. To name a few examples, the electronic device may be the electronic device 100, or another digital camera, a smart phone, a computer of any type, or a smart television that has access to the images.
Post-production may be useful when a common object in the scene appears at different positions in the images. There are several potential causes of this situation, such as the fact that the electronic device 100's angle of view may change with the focal distance, that the electronic device 100 fails to remain still at step 240, and that the object is moving when the electronic device 100 is performing step 240.
For example, at step 420, the electronic device may extract a first feature point from coordinates (x1, y1) of image 301 and a second feature point from coordinates (x2, y2) of image 302. Then, at step 440, the electronic device may match the two feature points because they seem to represent to the same point in the scene, such as the tip of the mountain 340. Next, at step 460, the electronic device may align images 301 and 302 by moving the both the first and second feature points to coordinates (x3, y3). After step 460, the electronic device may have a new image generated based on image 301 and a new image generated based on image 302, and the two new images are better aligned with each other.
As a second example of the post-production activities, an electronic device may use two images of the scene to interpolate/extrapolate another image of the scene. The two images may be two of the images captured at step 240, or two aligned images of the scene. The two images and the interpolated/extrapolated image are of the same scene, but correspond to three different focal distances.
Furthermore, with multiple images of the scene but at different focal distances, the electronic device may give its user more choices and let the user to freely select therefrom. In effect, this allows the user to refocus a photo after the photo has been taken and the user is no longer before the scene. For example, seeing one of the images displayed by the electronic device, the user may instruct the electronic device to display another image of the same scene that is taken at another focal distance.
At step 520, the electronic device display one, e.g. a random one, of the images. Then, at step 530, the electronic device receives a refocus instruction from the user. The refocus instruction may instruct the electronic device to display another one of the images that has a either a shorter or a longer focal distance than that of the image displayed at step 520. Next, at step 540, the electronic device selects another one of the images based on the refocus instruction and the focal distance values of the images. Finally, at step 550, the electronic device displays the selected image in place of the image displayed at step 520.
For example, if the electronic device displays image 302 at step 520, it may allow the user to issue a refocus instruction to either decrease or increase the focal distance. If the user issues a refocus instruction to decrease the focal distance at step 530, the electronic device may select image 301 at step 540 and display image 301 at step 550. If the user issues a refocus instruction to increase the focal distance at step 530, the electronic device may select image 303 at step 540 and display image 303 at step 550.
If the electronic device displays image 301 at step 520, it may allow the user to issue a refocus instruction to increase (but not decrease) focal distance. If the user issues a refocus instruction to increase the focal distance at step 530, the electronic device may select image 302 at step 540 and display image 302 at step 550. If the electronic device displays image 303 at step 520, it may allow the user to issue a refocus instruction to decrease (but not increase) focal distance. If the user issues a refocus instruction to decrease the focal distance at step 530, the electronic device may select image 302 at step 540 and display image 302 at step 550.
The focusing value of an area of image indicates to what extent the visual content therein is in focus. For example, the larger the focusing value, the clearer the visual content may seem; the smaller the focusing value, the more blurred the visual content may seem. To name a few examples, the focusing value may be, or be generated based upon, a contrast value or a sharpness value of the visual content.
Then, at step 620, the electronic device receives an area-selection instruction that selects one of the areas. Next, at step 630, the electronic device selects one from the images based on the focusing values of the selected area in the images. Finally, at step 640, the electronic device displays the selected image.
For example, to facilitate step 620, the electronic device may display a random one of images 301, 302, and 303 on a touch screen and allows the user to use the touch screen to select one of areas I, II, Ill, and IV. For example, if the user selects area I, the electronic device may elect one from images 301, 302, and 303 at step 360 based on the focusing values represented by the rectangles in
The aforementioned embodiments do not require expensive hardware, such as complicated optical system. Without much additional hardware costs, the embodiments may allow a user to refocus a photo after the photo has already been taken.
In the foregoing detailed description, the invention has been described with reference to specific exemplary embodiments thereof. It will be evident that various modifications may be made thereto without departing from the spirit and scope of the invention as set forth in the following claims. The detailed description and drawings are, accordingly, to be regarded in an illustrative sense rather than a restrictive sense.
Claims
1. A method performed by an electronic device capable of capturing images, comprising:
- receiving a shutter instruction; and
- automatically capturing a plurality of images of a scene using a plurality of different focal distances, respectively, in response to the shutter instruction.
2. The method of claim 1, wherein the step of automatically capturing the images is performed devoid of user intervention.
3. The method of claim 1, wherein the step of automatically capturing the images comprises:
- automatically enabling the electronic device to get the focal distances one by one and capturing and storing the images of the scene one by one.
4. The method of claim 1, further comprising:
- recording a focal distance value of each of the images, wherein the focal distance value corresponds to the focal distance used in capturing the image;
- displaying one of the images;
- receiving a refocus instruction;
- selecting another one of the images based on the refocus instruction and the focal distance values of the images; and
- displaying the selected image.
5. The method of claim 1, further comprising:
- recording a plurality of focusing values of a plurality of areas, respectively, of each of the images;
- receiving an area-selection instruction that selects one of the areas;
- selecting one from the images based on the focusing values of the selected area in the images; and
- displaying the selected image.
6. The method of claim 1, further comprising:
- extracting feature points from at least two of the images;
- matching the feature points; and
- aligning the at least two images using the matched feature points as reference points.
7. The method of claim 1, further comprising:
- generating an additional image of the scene based on two of the images of the scene through interpolation or extrapolation, wherein the additional image and the two images correspond to three different focal distances.
8. An electronic device capable of capturing images, comprising:
- a user interface;
- an actuator;
- an image sensor;
- a storage device; and
- a processor, coupled to the user interface, the actuator, the image sensor, and the storage device, and configured to:
- in response to a shutter instruction the user interface receives, automatically control the actuator to enable the electronic device to get a plurality of focal distances, the image sensor to capture a plurality of images of a scene using the focal distances, respectively, and the storage device to store the images.
9. The electronic device of claim 8, wherein in response of the shutter instruction, the processor is configured to control the actuator, the image sensor, and the storage device devoid of user intervention.
10. The electronic device of claim 8, wherein the processor is further configured to:
- control the storage device to record a focal distance value of each of the images, wherein the focal distance value corresponds to the focal distance used in capturing the image;
- control the user interface to display one of the images;
- control the user interface to receive a refocus instruction;
- select another one of the images based on the refocus instruction and the focal distance values of the images; and
- control the user interface to display the selected image.
11. The electronic device of claim 8, wherein the processor is further configured to:
- control the storage device to record a plurality of focusing values of a plurality of areas, respectively, of each of the images;
- control the user interface to receive an area-selection instruction that selects one of the areas;
- select one from the images based on the focusing values of the selected area in the images; and
- control the user interface to display the selected image.
12. The electronic device of claim 8, wherein the processor is further configured to:
- extract feature points from at least two of the images;
- match the feature points; and
- align the at least two images using the matched feature points as reference points.
13. The electronic device of claim 8, wherein the processor is further configured to:
- generate an additional image of the scene based on two of the images of the scene through interpolation or extrapolation, wherein the additional image and the two images correspond to three different focal distances.
14. A machine readable storage medium storing executable program instructions which when executed cause an electronic device to perform a method comprising:
- receiving a shutter instruction; and
- automatically capturing a plurality of images of a scene using a plurality of different focal distances, respectively, in response to the shutter instruction.
15. The machine readable storage medium of claim 14, wherein the step of automatically capturing the images is performed devoid of user intervention.
16. The machine readable storage medium of claim 14, wherein the step of automatically capturing the images comprises:
- automatically enabling the electronic device to get the focal distances one by one and capturing and storing the images of the scene one by one.
17. The machine readable storage medium of claim 14, wherein the method further comprises:
- recording a focal distance value of each of the images, wherein the focal distance value corresponds to the focal distance used in capturing the image;
- displaying one of the images;
- receiving a refocus instruction;
- selecting another one of the images based on the refocus instruction and the focal distance values of the images; and
- displaying the selected image.
18. The machine readable storage medium of claim 14, wherein the method further comprises:
- recording a plurality of focusing values of a plurality of areas, respectively, of each of the images;
- receiving an area-selection instruction that selects one of the areas;
- selecting one from the images based on the focusing values of the selected area in the images; and
- displaying the selected image.
19. The machine readable storage medium of claim 14, wherein the method further comprises:
- extracting feature points from at least two of the images;
- matching the feature points; and
- aligning the at least two images using the matched feature points as reference points.
20. The machine readable storage medium of claim 14, wherein the method further comprises:
- generating an additional image of the scene based on two of the images of the scene through interpolation or extrapolation, wherein the additional image and the two images correspond to three different focal distances.
Type: Application
Filed: Nov 6, 2012
Publication Date: May 8, 2014
Applicant: MEDIATEK INC. (Hsin-Chu)
Inventor: Chen-Hung Chan (Taoyuan County)
Application Number: 13/669,468
International Classification: H04N 5/228 (20060101); G03B 13/00 (20060101);